Multi-segment generation allocating systems



Feb. 5, 1963 N. COHN MULTI-SEGMENT GENERATION ALLOCATING SYSTEMS I 5Sheets-Sheet 2 Filed May 5, 1961 m: w i 1 All; u

QJ b umm zlrw KwPPm n.

Feb. 5, 1963 N. COHN 3,076,898

MULTI-SEGMENT GENERATION ALLOCATING SYSTEMS Filed May 3, 1961 5Sheets-Sheet 5 I BASE 8 A 8\B 8\ c PolNT SETTER 26A Feb. 5, 1963 N. COHNMULTI-SEGMENT GENERATION ALLOCATING SYSTEMS 5 Sheets-Sheet 4 Filed May3, 1961 A 6 M; a C M 4 M m. m m m m m\ m M 5 C M. 2 2 2 m m Feb. 5, 1963N. COHN MULTI-SEGMENTGENERATION ALLOCATING SYSTEMS 5 Sheets-Sheet 5Filed May 5, 1961 mw w 3,976,893 MULTKSEGMENT GEI IERATIQN ALLGQATEIGSYSTEMS Nathan (Cairn, .lenirintown, Pa, assignor to Leeds and Northrupornpany, Philadelphia, Pa, a corporation of Pennsylvania Fitted May 3,Met, Ser. No. 16 7,47 18 Qiairns. (Qt. sen--57 This invention relates tosystems for allocating the total generation desired of a group ofgenerating sources among the individual sources in accordance with apreset loading schedule.

In my Patent 2,773,994 there is disclosed generation allocation systemswherein the loading schedule for each participating source is preset bymeans of basepoint and participation setters. in the present invention,the need for manually-operated participation setters is eliminated, andinstead the participation values are automatically computed andautomatically introduced into appropriate points of the allocationnetworks. With the present invention, basepoints only for each sourceare preset, simplitying correspondingly the setting of allocationschedules by the load dispatcher.

In accordance with the present invention, there are produced a pluralityof fixed signals representative of upper and lower basepoint generationsof the individual generating sources. There are also produced fiedsignals representative of the upper and lower area breakpointgenerations of all generating sources of the group. In normal operation,these area breakpoint generations are equal to the sum of thecorresponding 'b-asepoint genera tions of the individual sources. Theaforesaid signals are effectively combined with a signal representativeof the total generation to be allocated to produce a plurality ofgeneration-allocation signals each representative of the extent to whichthe generation of the corresponding source should be above its lowerbasepoint or below its upper basepoint. To each of suchgeneration-allocation signals may be combined a fixed signalrepresentative of the lower or upper 'basepoint of the correspondingsource so that the resultant signal is representative of the generationrequired of that source to put it on schedule.

Also in accordance with the present invention, when the loading scheduleis of the multisegment type, there are provided switching meanseffective upon change of total generation through an area breakpoint, toshift to adjacent allocation segments by transferring to the upper andlower basepoints of the source schedule segment then to be in etfect. Onoccurrence of such a transfer in the direction of increasing generation,the prevailing upper basepoint becomes the new lower basepoint. Onoccurrence of such a transfer in the direction of decreasing generation,the prevailing lower basepoint becomes the new upper basepoint.

A feature of the present invention is that the basepoint setters withwhich source allocation schedules are preset may be calibrated to readdirectly in megawatts or other measure of source output, and there-setting of one basepoint setter does not affect the direct readingcalibration of the other basepoint setters.

The invention further resides in computing circuits having features ofcombination and arrangement hereinafter described and claimed.

For a more detailed understanding of the invention as embodied inseveral embodiments thereof, reference is made in the followingdescription of them to the attached drawings in which:

FIG. 1 represents a specific example of a multi-segment loading schedulefor the stations of a generation area;

FIG. 2 is the circuit diagram of one form of the invention for producinggeneration-allocation signals;

3,@7fi,893 ifatented Feb. 5, 1963 FIG. 3 is the circuit diagram of anarrangement for combining one of the generation-allocation signalsproduced by the system of FIG. 2 with a basepoint signal;

FIG. 4 illustrates an arrangement for presetting the basepoints of anindividual generating source into various networks of FIG. 2 and FIG. 3;

FIG. 5 is the circuit diagram of another system embodying the inventionto provide generation-allocation signals representative of the requiredgeneration of the generating sources;

FIG. 6 illustrates an arrangement for presetting the source basepointsinto various networks of the system of FIG. 5; and

FIG. 7 is the circuit diagram of another system embodying the inventionto provide signals respectively representing the required generation ofthe individual sources to put them on schedule.

To achieve eflicient area operation while fulfilling an areas overallregulating requirements, the assignment of generation among stations ofthe area is sometimes in accordance with automatically computed loadingschedules, and sometimes in accordance with preset loading schedules.Such preset schedules or loading curves are generally prepared prior tothe operating period to which they are to apply. They take intoconsideration which generating facilities are available and what theirrelative capacities and incremental economies are. The schedules mayalso include the weight of other factors, such as loadings and losses ontransmission lines, locations of reserves, the ability of specificplants to respond to control action and stream flow or storageconditions where hydro-power is involved. A load dispatcher would havesuch curves or equivalent to assign generation to stations eitherautomatically or manually. These loading schedules may be simple orcomplex and they may be fixed or they may vary during the course of aday. For purposes of the present discussion, it will be assumed that theloading schedules of FIG. 1 are to apply to three stations of an area.Specifically, the curves 13, 25, 38 are respectively the loadingschedules of the stations S1, S2, S3 of an area. Quantitative magnitudeshave been assigned to these curves to facilitate the examination of howeach station is to be loaded as the total area generation varies. Alsothese quantitative values will be used later in the discussion toexplain how the computing circuit adjustments are made.

In the specific example under discussion, the total area generation isbroken into three segment groups: the first defined by thearea-generation breakpoints X and X the second defined by thebreakpoints X and X and the third defined by the breakpoints X and X Foreach area breakpoint, there is a corresponding set of station basepointswhose sum is equal to the area generation at the breakpoint. Forexample, for the lower breakpoint X of Segment II, the sum of thestation basepoints b is +50+80, totaling 209 megawatts; and for theupper breakpoint X of Segment II, the sum of the station basepoints 15is 12G+90+l40, totaling 350 megawatts.

The desired generation for any station within any segment or its loadingschedule can be computed from the equation b =station basepoint at lowend of segment b zstation basepoint at high end of segment Y areabreakpoint at low end of segment X =area breakpoint at high end ofsegment G =area generation N=area requirement G X =area regulationapropos for producing a series of output voltages or signals in numbercor-responding with the number of segments of the loading schedule andin magnitude respectively corresponding with the difference between theupper and lowerarea breakpoints which define the corresponding segmentsor each loading schedule. Specifically, the network 11 comprises a groupof slidewire's flir -12D connete'd in parallel across a suitable supplysource exempli-t-i'ed by transformer 13. The relatively adjustablecontacts 14A=14-D of the 'slide'wires 12A-12D are respectively connectedto the fixed contacts ISA-15D of the segment transfer switch 16. Thesl-idewires lZA lZD are each calibrated in terms of megawatts or othersuitable unit of power and are each respectively preset in accordancewith the area breakpoints of the loading schedule to be put into effect.In the specific example under dis cussion, the slidewires 12A-12D wouldbe respectively set to 150, 200, 350 and 450 megawatts correspondingwith the breakpoints X- X inclusive of the loading schedule shown inFIG. 1. The movable contacts 17A, 17B of switch 16 are stepped from onepair to another of the fixed contacts when the total area generationshifts from one segment to the next of the operating schedule. More"specifically, "when the total area generation is in Segment '1 of theloading schedule, the movable contacts 17A, MB "of switch 1'6 are inengagement with fixed contacts HA, 15B: when the total area generationis in Segment ll, the movable contacts 17A, 17B arein engagement withfixed contacts 15B, 15C: and when the total area generation is inSegment III, the movable contacts 17A, 17B 'a're'in engagement withfixed contacts 15C, 15D. Thus, with the 'slidewires 'l ZA-"IZD presentin correspondence "with the'succe's'siv'e area breakpoints, the outputvoltage e of network 11 as appearing between the contacts 17A, 17Bors'witen 1-6 corresponds, withthc difference between the-upper andlewer'area breakpoints of the schedule segment corres onding with theswitch position. Specificah 1y forjthe first switch position, thevoltage e represents '(X X' for the second switch position, voltage erepresents (X 26 and for th'e third switch switch position, voltage erepresents (X x Contacts 17A, 17B of the segmentnansrer switch may bemanually actu'a't'ed 'o'r step-actuated by any suitable'means responsiveto total area generation. For example, they may be actuated by'a cam 18,which is driven or otherwise controlled by wattmeter 19 responsive tototal area generation. The successive dwell sections or cam '18 may beadjustcd'to correspond in angular extent with the length of thecorresponding segment of the loading schedule. For the position of cam18 "shown in FIG. 2, the total area generation is in Segment II and theoutput voltage e ot network it represents the difference between thebreakpoints X X Alternatively, the switch 16 may be a's'tepping relaycontrolled by contacts set in accordance with area breakpoints in thepath of an actuating arm'p'ositio'ned by wattrnete'r 19. As anotheralternative, the stepping switch 16 may be effected by amplifier-relayarrangements, similar to those of FIG. 7, whose input circuits areresponsive to total generation and to the successiv'e area breakpoints.

The network also includes the networks 25A, 25B and 25C in numbercorresponding with the stations of the area. Since these networks aresimilar in composition and mode of operation, it should suffice todiscuss only one of them in detail. Each of them is for producing aseries of output voltages in number corresponding with the number ofsegments of the loading schedule of the corresponding station and inmagnitude corresponding with the difierence between the upper and lowerstation basepoints which define a corresponding segment of the stationloading schedule for that station. Specifically,

t the network 25A for station S1 comprises a group of slidewires EMA-26Dor equivalent adjustable impedances connected in parallel across asuitable supply source exemplified by transformer 27. The relativelyadjustable contacts 28A-28D of these slidewires are respectivelyconnected to the fixed contacts 29A-29D of segment trans fer switch 30-.The slidewircs 26A-26D are each calibrated in terms of megawatts orother unit of power and are each respectively preset in accordance withthe station basepoints of the loading schedule for station S1. In thespecific example under discussion, the slidewires 26A-26D would berespectively preset to 50, 70, and megawatts corresponding with thevalues of the basepoints b b for station S1 shown on curve 18 of FIG. 1.

The movable contacts 31A, 31B of switch 312 are positioned, as by cam13, relative to the successive pairs of fixed contacts 28A-28D inaccordance with the total area generation. Specifically for Segment 1 ofthe loading schedule is, the movable contacts 31A, 31B are respectivelyin engagement with fixed contacts 29A, 2E8: for Segment ll of theloading schedule 13, the movable contacts 31A, 31B respectively engagefixed contacts 29B, 2%): and for Segment ill of the loading schedule,the movable contacts 31A, 318 respectively engage fixed contacts 2%,2%).

Thus, with slidewi'res Edit-26D preset in accordance with the successivebasepoints for station S1, the output voltage a; of network 25A, asappearing across the contacts 31A, 31B of switch 3%, corresponds, foreach of the switch positions, with the difference between thecorresponding pair of station basepoints. Specifically, when the totalarea generation is in Segment 1 of the loading schedule, the movablecontacts 31A and 31B of switch are in engagement with fixed contacts 29Aand 29B, and the voltage 0 represents b b when the total area generationis in Segment ll, movable contacts 31A and 31B are in engagement withfixed contacts 29B and 29C, and the voltage e represents (b 17 and whenthe total area generation is in Segment Ill, movable con tacts 31A and31B are in engagement with fixed contacts ii /C and 2&1) and the voltagee represents (174b3).

The network 253 similarly includes a group of calibrated slidewires 36A3'6D which are respectively preset in accordance with the correspondingbasepoints b to b of loading schedule ZS for station S2. Theseslidewires are powered in parallel from transformer 37 or through asuitable supply source and their relatively adjustable contacts 38A-38Dare respectively connected 'to fixed contacts 39A39D of segment transferswitch 40. The movable contacts dlA, 41B of switch as are actuated bycam 18 or equivalent device responsive to total area generation. ForSegment 1 of loading schedule 28, the movable contacts 41A, 4313respectively engage fixed contacts 3QA, 39B so that the output voltage eof network 2513 represents the basepoint difference (la -b for SegmentII, the movable contacts MA, 413 respectively engage fixed contacts 3%,39C so that the voltage 2 represents the base'point difference (b b ofschedule 281 and for Segment Hi, the movable contacts 41A, 413respectively engage fixed contacts 39(3-391) so that the output voltagee represents the b'asep'oi-nt difference (o -b of the loading schedule28 for station S2. It will be understood from the foregoing that network25C similarly includes adjustable impedances preset in accordance withthe successive basep'oints h to b, of loading schedule 38 for stationSd,and that the switch as positioned by cam '18 or equivalent provides thatthe output voltage 6 of network 25C corresponds for each position ofswitch'Stl with the dilterence between the station basepoints of thecorresponding segments of the schedule 3S. I

The network 1? also includes 'a group of 'slidewire's 55A-55C in numbercorresponding with the number of station. These slidewires are connectedin parallel and excited by output voltage e of the area-breakpointnetwork 11. Thus, as each segment of the station loading schedulessequentially comes into efiect because of change in area generation,there is produced across each of the slidewires 55A-55C a voltage Whosemagnitude is representative of the difference between the upper andlower area breakpoints of that segment; for example, with the switch it?in the position shown, the voltage e across each of slidewiresfiSA-Sfifl represents the difference between the upper area brealrpointX and the lower area breakpoint X or" Segment ll of the loadingschedule.

'lhe output voltage c of the basepoint network 25A for station S1 iscompared with the voltage 2 across slidewire 55A by a self-balancingarrangement including ampli tier 60A and a servo-motor 61A in the outputcircuit thereof. In the input circuit of amplifier 60A, the voltage a;is in opposition to a fraction of voltage e, the magnitude of thefraction depending upon the position of slidewire contact 56A. Whenthese input voltages of amplifier 60A are not in balance, the resultingoutput energizes motor 1A to adjust the position of contact 56A untilbalance is obtaine and the position of the contact 55A corresponds withthe ratio in like manner, the output voltage 2 of the basepoint network253 for station S2 is compared with the voltage e across slidewire 553by the self-balancing arrangement including amplifier 60B andservo-motor 615. Similarly, the output voltage e of network 25C forstation S3 is compared with the voltage e across slidewire 550 by theself-balancing arrangement including amplifier 60C and servo-motor 61C.With the switches 1d, 30, 4t? and 50 in the position corresponding withSegment I of the loading schedules and with the amplifiers ti'llA-diiCin balance, the positions of contacts 56A, 56B, 56C each represents theratio for Segment 1 or" the corresponding station schedule: with theswitches in the position corresponding with Segment II of the loadingschedules and with the amplifiers in balance, the positions of contacts55A, 56B, 560 each represents the ratio for Segment ll of thecorresponding station schedule: an" with the switches in the positioncorresponding to Segment ill and with the amplifiers in balance, thepositions of contacts 56A, 56B, 56C each represent the ratio for Segmentill of the corresponding station schedule.

it will be recognized that these ratios each represent the slope of thecorresponding segment of the station loading schedule and are eachspecific forms of the ratio term out positions of the segment transferswitches 16, 30, 40 and $0 are indicated by Table I below:

it is now explained how these slope terms produced by network 10 areintroduced into and utilized in network 6s to compute the variousgenerations required of each of the stations to meet its loadingschedule.

The network 65 is similar to network 54 of FIG. 5 of my Patent 2,773,994to which reference may be had for a more detailed explanation of itscomposition. in brief, the subsidiary network 66 of FIG. 2 hereofincludes a slidewire 6? which is either center-tapped or connected inparallel to a center-tapped impedance or resistance 63 and is poweredfrom a suitable supply source exemplified by transformer 69. The contact70 is adjusted relative to its slidewire 57 so that the voltage Vbetween contacts 70 and the center-tap corresponds in polarity andmagnitude with the sense and magnitude of any existing area requirement(N). Such adjustment may be effected by an arearequirement meter 71,suitable forms of which are referred to in my aforesaid patent.

The subsidiary network 72 includes a slidewire 73 which is eiiectivelycenter-tapped by connection in parallel to the center-tapped resistance73a and is connected to a suitable supply source exemplified bytransformer 7d. The slidcwire contact 75 is adusted relative toslidewire '73 so that the voltage V between contacts 75 and thecenter-tap continuously corresponds in polarity and magnitude with theexisting area regulation (G -it' Such adjustment may be effected by anarea-regulation meter "1'6, a suitable form of which is shown in myaforesaid patent.

The station-participation slidewires "HA-77C are connected in circuitwith the networks so and 72 for traverse by a current which is thealgebraic sum of the arearequirement and the area-r'egulation and socorresponds with the quantity (G -K thi) of Equation 1.

The contacts 78A, 73B, 73C of slidewires "/IA, 77B, 77C are respectivelycoupled to the servo-motors 61A, 61B, 61C so that their positionsrespectively correspond with the slopes of those segments of the loadingschedules which are in effect. Thus, the efi'ective output voltages c e2 of the slidewires 75A, 75B, 75C respectively represent the extent towhich the generation of each of stations Sll, S2, S3 should be above itsapplicable basepoint to satisfy the area requirement and at the sametime maintain the desired sharin" of load between the stations as set bytheir loading schedules.

More specifically, each of these voltages is a solution of theexpression for the corresponding station taking into account the theneffective segment of its loading schedule.

To complete the solution of Equation 1, there is added in series witheach of the voltages e 6 2 a voltage whose magnitude represents thelower basepoint of the corresponding station for the schedule segmentthen in effect. In FIG. 3, there is shown an arrangement for adding suchbasepoint voltage to voltage a to produce an indicating or controlvoltage corresponding with the desired generation G for station 81. Fromthis figure and the following explanation thereof, it would be evidenthow the same arrangement may be applied for determining the desiredgenerations G and G for the other stations S2 and S3 of the area.

The basepoint circuits liiEA-BllC in number one less than the totalnumber of station basepoints respectively include the slidewires SEA-MCwhich are powered from separate supply sources exemplified bytransformers dbl-32C. As indicated in PR 4, the slidewire 81A ismechanically coupled to slidewire 26A of network 25A (FIG. 1) so thatthe first basepoint of station 81 is simultaueously set into networks25A and 80A: the slidewire 81B is mechanically coupled to slidewire 26B(PEG. 1) so that the second basepoint of station 81 is simultaneouslyset into networks 253 and 30B: and slidewire tilt) is mechanicallycoupled to slidewire 26C so that the third basepoint of station 81 issimultaneously set into network 25C and dtlC. Since this is athree-segment schedule, there is no need for a fourth slidewire coupledto slidewire 26D.

The relatively adjustable contacts llZlA, 83B, 83C of the slidewires31A, 81B, 81C are respectively connected to the fixed contacts 34A, 843,MC of the segment transfer switch which is actuated by the schedule cam18 or equivalent in accordance with total area generation. Thus, whenthe total area generation is in the first segment of the station loadingschedule, the movable contact 86 of switch S5 engages the fixed contact84A so that the output voltage G 'appearing between terminals 87A, 83Aand representative of the desired generation for station 82 is the sumof the voltage c and the preset voltage e corresponding with the firstbasepoint of the schedule for station 81. In like manner, when movablecontact dd engages fixed contact 843, the output voltage G is the sum ofany existing voltage e and the preset voltage e corresponding With thesecond basepoint of the schedule for station 81. Similarly when themovable contact 86 is in engagement with fixed contact 840, the outputvoltage G is the sum of any voltage e and the preset voltage ecorresponding with the third basepoint for station S1.

Thus, at all times the signal G represents the desired generation ofstation S1 to maintain its scheduled share of total area generation. Asimilar arrangement (not shown) of the basepoint circuits and thesegment switch is provided for connection to each of the otherparticipation slidewires 77B, 77C similarly to provide signals G Grespectively representing the desired generation of stations S2 and S3.The desired generation signals G G and G may be transmitted over anysuitable form of telemetering to generation stations of the area forcontrol of their generation or they may be compared with signalsrepresenting actual generation of the stations and the resulting errorsignals transmitted to the respective stations for control of theirgeneration to reduce the error signals to zero. When a station consistsof a single generating unit, the transmitted signal may be utilizedautomatically to control the input, to the station unit by varying thethrottle valve or gate of the prime mover, directly or through a speedgovernor, or by varying the boiler input. Various known arrangements,including that shown in my aforesaid patent, are suited for utilizingsuch transmitted signal to control the generation of stations and units.

When the station comprises two or more units, an arrangement such asshown in FIGS. 2 and 3 may be utilized at the station to divide itsgeneration requirement among the generating units upon the bases ofunit-loading schedules similar to those of FIG. 1 except that the totalgeneration is that of the station and that the individual generationsare those of generating units. The preset breakpoints will now be thoseof total station generation and the preset basepoints will be those ofindividual generating units. The resulting desired generation signals ofthe units may each be utilized to control the generation of the unit asabove briefly described. All of the preceding discussion of FIGS.

1 to 4 will apply except that it will be at station level rather than atarea level. It is to be noted that with the arrangement of FIGS. 2 and3, unlike that shown in my aforesaid patent, the multi-segment loadingschedule is established without the use of preset participation setters,eing preset instead by basepoint setters and by breakpoint setters, eachof which may be calibrated to be direct reading in output. Theparticipation values for each source are automatically computed andinjected into the allocation circuits in the manner already described.

It should be noted that area breakpoints, being equal to the sum ofcorresponding station basepoints, need not be separately set as in FIG.2, but may be derived from a summation of additional slidewires on thebasepoint setters, as will be discussed later in conjunction with FIG.5.

Equation 1 may be rewritten in the form es=bd+(b.bd f3i and in such formis solved by the computer circuit arrangement shown in FIG. 5 whichutilizes a single servo-motor and which includes no breakpoint settersby taking advantage of the fact that the lower breakpoint of aparticular segment is scheduled to the sum of the lower basepoints andthat the upper breakpoiut of that segment is equal to the sum of theupper basepoints. Thus, in setting up the loading schedules an operatorneed only set the station basepoints at area level and unit basepointsat station level.

The first basepoint circuits EMA-C of FIG. 5, in number correspondingwith the number of stations, respectively include the slidewires 91A-91Cand are separately powered from suitable supply sources exemplified bytransformers QZA-dZG. The slidewire contacts 93A-93Q are set relative totheir respective slidewires each in accordance with the first basepointof the schedule of the corresponding station. The outputs of thecircuits QttA-dllC, as indicated, are connected in series so that theirjoint output as measured between contact 930 and lead 94 correspondswith the sum of the first basepoints of the stations.

The second basepoint circuits 95A-95C respectively include theslidewires 96A-96C and are separately powered from supply sourcesexemplified by transformers 97A- 97C. The contacts 98A-98C are setrelative to their respective slidewires, each in accordance with thesecond basepoint of the corresponding station. The outputs of thecircuits 5A-95C are connected in series so that their joint output asappearing between contact 980 and lead 94 corresponds with the sum ofthe second basepoints. The third basepoint circuits ltltlA-llltlCrespectively include the slidewires ltllA-llllC and are separatelypowered from supply sources exemplified by transformers lll2A-1ll2C. Thecontacts lllSA-WSC are set relative to their respective slidewires, eachin accordance with the third basepoint of the corresponding station. Theoutputs of the circuits ltlllA-lllllC are connected in series so thatthe voltage between contact 1930 and lead 94 represents the sum of thethird basepoints.

The fourth basepoint circuits ltl5A-ldC respectively include theslidewires llllGA-ltldC and are separately powered from supply sourcesexemplified by transformers ltl7A-l07C The contacts TWA-168C are setrelative to their respective slidewires, each in accordance with thefourth basepoint of the corresponding station. The outputs of thecircuits 1tl5A-1tl5C are connected in series so that the voltage betweencontact 108C and lead 94 represents thesum of the fourth basepoints ofthe stations.

The output contacts 93C, 98C, 103C, 1080 of the corresponding basepointcircuits 90C, 95C, 1096, 105C are respectively connected to the fixedcontacts lltlA-llltlD of the segment transfer switch 111. The movablecontacts 112, 113 of switch 111 are connected to the terminals ofslidewire 114 which is center-tapped or shunted by a center-tappedimpedance 115. For each position of switch 111, the voltage from contact112 to lead 94 represents X, and the voltage from contact 113 to lead'94 represents X Since in the circuit loop from contact 112 to lead 94and back to contact 113 those voltages are in opposition, the voltagebetween the contacts 112, 113 represents the difference X -XSpecifically, with the switch 11 in its econd segment position shown inFIG. 5, the voltage E representing the difference (X X between the sumof the third basepoints of stations Sit-S3 and the sum of the secondbasepoints of stations 81-33 is applied to the slidewire 114. Similarly,when the switch H1 is in its first segment position, the slidewire 114has applied to it the voltage E representing the difference (X X betweenthe sum of the second basepoints of stations 51-83 and the sum of thefirst basepoints of stations SLSE, and when the switch 111 is in itsthird segment position, the slidewire i1 3 has applied to it the voltageE representing the difference (X X between the sum of the fourthbasepoints of stations 811-53 and the sum of the third basepoints ofstations Sl-S3.

The slidewire 114 and its center-tapped resistor form a network 126which is included in network 65, which as in the system of FIG. 2,produces voltages V and V re spectively representative of arearequirement (N) and area regulation (G -K The servo-motor 117 undercontrol of amplifier 118 adjusts the position of slidewirc 3114 tomaintain balance of the algebraic sum of voltages V V and the unbalancedvoltage of network 116 which is proportional to voltage E Thus, theposition of contact 119 represents the quantity G X :N X XT of Equation1A As now explained, this quantity is effectively multiplied for eachsegment of the loading schedule of each station, by a factorrepresenting the diiference between the upper and lower basepoints ofthat segment. In the network 12 9, the slidcwires REA-121D are setrelative to their contacts f22A-l22l) in accordance with the successivebasepoints of the loading schedule for station S1. The slidcwiresl23A-l23D are set relative to their contacts 124A-l2dD in accordancewith the successive basepoints of the loading schedule for station 52.The slidcwires 125A-l25l) are set relative to their contacts 126A-ll26Din accordance with the successive basepo-ints of the loading schedulefor station S3.

The corresponding basepoint slidcwires for each station are in parallelto one another so that the voltage between the successive pairs ofslidewire contacts is proportional to the difference between thecorresponding basepoints of that station. For example, the voltage ebetween contacts 1263 and 126A is proportional to (b2-b1)i the voltage(2 between contacts 126C and 1263 is proportional to (h -b and thevoltage e between contacts 126D and 126C is proportional to (b -b To theend that the current through each of the aforesaid basepoint slidcwiresof network 12% be proportional to the quantity they are supplied fromthe network 130. This network includes slidewire 131 which iseffectively center-tapped by the center-tapped shunt resistor 131. Theslidewire 131 is powered from a suitable power supply source exemplifiedby transformer 133 and its contact 134 is ad justable by the servo-motor117. Thus, the output voltage e applied to all of the slidcwires ofnetwork 120 is proportional to the aforesaid quantity.

Thus, the aforesaid voltages e e e respectively represent the ditferencebetween the successive pairs of basepoints for station S3 times theaforesaid quantity. Specifically:

e31 represents (Zn-b G X2iN] 6113 represents b -b X3 X it) and 6represents (b bs) To obtain for each of the schedule segments a voltagewhich represents the desired generation G for station S3 as defined byEquation 1A, there is added to each of the aforesaid voltages, e e 6 avoltage which represents the lower basepoint of the correspondingsegment. The basepoint circuits 135A and 135C, in number one less thanthe total number of basepoints for station S3, respectively include theslidcwires BSA-136C which are powered from separate supply sourcesexemplified by transformers TiS'iA-l37C. As indicated in PEG. 6, theslidewire 136A is mechanically coupled to slidcwires 91C and 125A sothat the first basepoint of station S3 is simultaneously preset innetworks 135A, 94%) and 129: the slidewire 136B is mechanically coupledto slidcwires- 96C and 1253 so that the second basepoint of station S3is simultaneously preset in networks 135B, C and 12d; and the slidewire1360 is mechanically coupled to slidewires 181C and C so that the thirdbasepoint of station S3 is simultaneously preset in networks C, seas and12%.

The relatively adjustable contacts TWA-138C of slidewires 13dA-136C ofnetworks BSA-135C are respec tively connected to the fixed contacts139A-13C of the egment transfer switch f it) which is actuated by theschedule cam 13 or equivalent device stepped in accordance with totalarea generation. The relatively adjustable contacts 125A126D of theslidcwires 125A-125D of network 126 are connected to the fixed contacts141A-141D of transfer switch 143. Thus, when the total area generationis in the first segment of the loading schedule for sta tion S3, thmovable contact 142 of switch 140 engages the fixed contacts 139A, 141Aand movable contact 143 of switch 14d engages fixed contact 1413 so thatthe output voltage G between terminals 144, is the sum of the aforesaidvoltage (2 and a preset voltage e corresponding with the first basepointfor station S3. For the second segment of the loading schedule forstation S3, the movable contact 142, as shown, engages the fixedcontacts 13?]3 and 1413 and the movable contact 143 engages fixedcontact 141C so that the output voltage G is the sum of the aforesaidvoltage 2 and a preset voltage e corresponding with the second basepointfor station S3. For the third segment of the loading schedule forstation $3, the movable contact 142 of switch Mil engages the fixedcontacts 141C and 139C and the movable contact 143 engages the fixedcontact 141D so that the output voltage 6 is the sum of the aforesaidvoltage e and a preset voltage e corresponding with the third basepointfor station S3.

Thus, at all times the signal G represents the desired generation ofstation S3 to keep it on its schedule for desired participation in thetotal area generation and area requirement. A similar arrangement (notshown) of basepoint circuits and a segment transfer switch is providedfor the basepoint slidcwires 121A121D for station S1 and is provided forbasepoint slidcwires 123A- 123D for station S2 similarly to providestation control signals (5S1 G respectively representing the desiredgeneration of stations S1 and S2. The signals G Gsz, G may betransmitted over any suitable form of elemetering channel to thecorresponding stations of the area for control of their individualgenerations. When a station consists of a single generating unit, suchstation control signal may be used to control the input to thegenerating unit of the station by varying the throttle valve or gate ofits prime mover directly or through a speed governor or by varyingboiler input. When the station comprises two or more generating units,an arrangement similar to that shown in FIG. 5 may be utilized at thestation to divide its total generation among the units of that screensstation on the basis of unit loading schedules similar to those of FIG.1 except that the total generation is that of the station and that theindividual generations are those of its generating units. In such case,the preset basepoints will be those of the generating units and all ofthe preceding discussion of FIGS. 5 and 6 will apply except that it willbe for station level rather than area level.

With the arrangement of FIG. 5 as used at either area or station level,the multi-segment load schedule is established solely by basepointsetters, which may be calibrated directly in source output.

In the arrangement of FIG. 7, like that of FIG. 2, the multi-segmentloading schedule is established at area level by area breakpoint settersand station basepoint setters and isestablished at station level bystation breakpoint setters and unit basepoint setters.

The area breakpoint network 150 comprises the slidewires BIA-151D, innumber corresponding with the numbed of adjustable area breakpoints,connected in parallel across a suitable supply source exemplified bybattery 152'. The slidewires MIA-151D are each calibrated in terms ofmegawatts or other suitable unit of power and are preset with respect totheir relatively adjustable contacts l53A-l53D'in accordance with thearea generation breakpoints of the loading schedules to be put intoeffect. The amplifiers llS lA-lSdC have their ungrounded input'terminalsrespectively connected through input resistors ESSA-155C to theslidewire contacts ESSA-153C These input terminals are also respectivelyconnected through input resistors Hort-156 C to the contact 157 ofslidewire 158 which is powered from a suitable supply source exemplifiedby battery 16%. The position of contact 157 relative to its slidewire158 is controlled by the meter 149 which is responsive to the existingarea generation as modified by any existing area requirement, i.e., to(G iN) or total generation required of the area. Otherwise stated, theoutput voltage of network 159 as applied to input line 161 common toamplifiers 154A- 1546 varies with the total generation required of thearea, hereinafter referred to as area destination, and the outputvoltages of network as respectively applied to the amplifiers EMA-195Crepresent the successive area breakpoints.

Thus, in the input circuit of each amplifier IS-tA-lS lC there arecompared two signals respectively representing the corresponding areabreakpoint and the area destination as above defined. When the magnitudeof the area breakpoint signal is the lesser of the two, the amplifieroutput energizes the corresponding one of the relays 16-2A-162Crespectively in the output circuits of amplifiers 154A-l5d for purposesnow explained.

With all relays deenergized, as is true when area destination is lessthan the first, area breakpoint, the voltage on bus 163 represents thefirst area breakpoint and the bus tea is at ground potential. For thisstate of the relays, the bus 163 is connected to the movable contact153A of the first area breakpoint slidewire 151A through a path providedby the normally-closed contacts 165A, 165B, 165C of the relays; the bus164 is connected to ground through the normally-closed contacts 166A,166B, 166C of the relays.

With relay 162A energized and relays 162B, 1620 deenergized, as is truewhen area destination is greater than the area breakpoint set by contact153A but less than the area breakpoint set by contact 1533, the voltageon bus 163 represents the next higher area breakpoint and the voltage onbus 164 represents the next lower area breakpoint. Forthis state of therelays, the bus 163 is connected to the movable contact 1533 of thesecond breakpoint slidewire 15113 through the normally-closed contacts1656, 16513 of relays 162C, 16213 and the now closed back contacts 167Aof relay 162A; and the bus 16-4 is connected to the movable contact 153Aof the first breakpoint slidewire 151A through the normally-closed con-12.2 tacts 166C, 1663 of relays 162C, 162B and the now closed backcontacts 168A of relay 162A.

With relays 162A, 162 B energized and relay 1620 deenergized, as is truewhen area destination is greater than the breakpoint set by contact 1538but less than the breakpoint set by contact 1153C, the voltage on bus163 again represents the next higher breakpoint and the voltage on bus164 represents the next lower breakpoint. For this state of the relays,the bus 163 is connected to the movable Contact 153C of the breakpointslidewire 15H) through the normally-closed contacts 165C of relay 162Cand the now closed back contacts 167B of relay 16213: and the bus 164 isconnected to the movable contact 1538 of the second 'breakpointslidewire 15113 through the normally-closed contacts 166C of relay 162Cand the now closed back contacts 1MB of relay ltd-2B.

With all relays deenergized, as is true when area destination is greaterthan the breakpoint set by contact 153, the voltage on bus 163represents the next higher breakpoint and the voltage on bus ltd irepresents the next lower breakpoint. For this stage of the relays, thebus lid? is connetced to the movable contact 153D of the breakpointslidewire 151D through the now closed back contacts 1.670 of relay 162C:and the bus 16 is connected to the movable contact 153C of thebreakpoint slidewire 151C through the now closed back contacts 168C ofrelay 162C.

From the foregoing it should be clear that for each segment of theloading schedule, the voltage on bus 163 represents the upper breakpointX of that segment and that the voltage on bus res represents the lowerbreakpoint X; of that segment.

The X voltage on bus 163 is applied to the ungrounded input terminal ofamplifier 17% through input or summing resistor 171. The X voltage onbus 164%, after reversal of its polarity, is also applied to theungrounded input terminal of amplifier 174% through input or summingresistor 1729. The aforesaid polarity reversal of the X voltage isefiectcd by the operational amplifier 3732. The unreversed X voltage isapplied through input resistor 1'74- to the ungrounded input terminal ofamplifier 1'73. A negative teed-back resistor 175 connected from theoutput terminal of amplifier 173 to its ungrounded input terminalinsures a linear proportional relationship between its input and outputvoltages respectively corresponding with X and +X The net input voltageof amplifier 17th thus corresponds in magnitude with the differencebetween the upper and lower breakpoints of the schedule segment in use.A linear proportional relationship between such net input voltage andtheoutput voltage of amplifier 170 is insured by the negative feedbackresistor 176.

The output voltage of the operational amplifier 17% is opposed to theeffective output voltage of the network 177 including the slidewire 178and a suitable power source exemplified by battery 179. When thesevoltages are not in balance, the output of the amplifier 189* to whichthey are applied energizes the servo-motor 181 to effect a balancingadjustment of contact 182 relative to its slidewire 173. Thus, theangular position of shaft 183 which is concurrently adjusted byservo-motor 181, represents the difference (X X between the upper andlower breakpoints of the schedule segment in effect. As will laterappear, this shaft introduces the quantity (X 'X into computer circuitsrespectively corresponding with the stations of the area.

The unreversed X voltage on bus 164 is applied through input resistor185 to the ungrounded input terminal of amplifier 186. To the sameterminal, there is applied through input resistor 187 the voltage on bus161 which, as above stated, represents area destination. Thus, the netinput of amplifier 186 represents the difference between areadestination and the next lower area breakpoint. To insure linearproportionality between such net input and the output of amplifier 186,the resistor 138 13 is connected from the output terminal to theungrounded input terminal to provide negative feedback.

The output voltage of the operational amplifier 136 is opposed to theeffective output voltage of the network 1% including the slidewire Niand a suitable power source exemplified by battery 192. When thesevoltages are not in balance, the output of amplifier 192% to which theyare applied energizes the servo-motor 19 5- to el fect balancingadjustment of contact 195 relative to its slidewire 19!. Thus, theangular position of shaft res, which is concurrently adjusted byservo-motor 194, represents the difference (G iNX between areadestination and the next lower breakpoint. As will later appear, thisshaft introduces the quantity (G iN-X into circuits which respectivelycompute the desired generations of the stations of the area. Since suchcomputer circuits are identical, only the one for station S1 need beillustrated and described.

The station basepoint network sea comprises the slidewires EMA-2121B, innumber corresponding with the number of adjustable station basepoints,connected in parallel across a suitable supply source exemplified bybattery 2&2. The slidewires ZllTiA-Zilll) are each callbrated in termsor megawatts or other unit or" power and are preset with respect totheir respective relatively adjustable contacts 2fi3A-2ll3l) inaccordance with the basepoints of the station-loading schedule ineffect.

With all of relays 162A-152C deenergized, the voltage on bus 2%represents the first adjustable basepoint of station 51 and the bus 2%is at ground potential. For this state of the relays, the bus 2% isconnected to th contact 266A of the basepoint slidewire Zill through thenormally-closed contacts ZiWA-ZWC of the relays: the bus 2% is connectedto ground through the normallyclosed contacts ZllriA-ZilfiC of therelays.

With relay 162A energized and relays 162B, 162C deenergized i.e., whenthe area destination is greater than the setting of contact 151A, thevoltage on bus 2% represents the upper basepoint of station Si and thevoltage on bus 2% represents the lower basepoint of station 81 for theapplicable segment of the loading curve. For this state of the relays,the bus 295 is connected to the contact 2933 of the basepoint slidewire2MB through the normally-closed contacts 297C, 2MB of relays 162C, 1623and the now closed back contacts ZWA of relay 162A: the bus 2% isconnected to the contact 253A of the basepoint slidewire 2331A throughthe normally-closed contacts ZdhC, seas of relays 162C, 1623 and the nowclosed back contacts ZlfiA of relay 162A.

With relays 152A, 1623 energized and relay 162C deenergized, the voltageon bus ass again represents the upper base point of station Si and thevoltage on bus 2% represents the lower basepoint of station S1 of theapplicable segment of the loading curve. For this state of the relays,the bus 2% is connected to the contact ZilEQ of the basepoint slidewireZillC through the normally-closed contacts ZlliC of relay 162C and thenow closed back contacts ZfifiB of relay 16213: the bus 2% is connectedto the contact ZllSB of the basepoint slidewire ZiilB through thenormally-closed contacts 298C of relay and the now closed back contacts21913 of relay 1623.

With all of the relays leIZA-l62B energized, the voltage on bus 265again represents the upper basepoint of station Si and the voltage onbus 2% represents the lower basepoint of station Si. For this state ofthe rela s, the bus 2% is connected to contact 2631) of the basepointslidewire ZlliD through the now closed back contacts 2tl9C of relay162C: the bus 2% is connected to the contact 263C of the third basepointslidewire ZillC through the now closed back contacts ZillC of relay162C.

From the foregoing, it should be clear that for each segment of theloading schedule for station S1, the voltage on bus 235 represents theupper basepoint b of that segment and that the voltage on bus 2th;represents the lower basepoint b oi that segment.

iii.

The b voltage on bus 2'65 is applied to the ungrounded input terminal ofamplifier Zil through input resistor 212. The b voltage on bus 2% isalso applied, after reversal of its polarity, to the ungrounded inputterminal of amplifier Ell through input resistor 213. The aforesaidpolarity-reversal oi the b voltage is effected by the operationalamplifier The unreversed b voltage is applied through input resistor 216to the ungrounded terminal oi amplifier 215. The negative feedbackresistor 21? insures a linear proportional relationship between theinput and output voltages of amplifier 215, such voltages respectivelycorresponding with +b and b The net input voltage of amplifier 211 thuscorresponds in magnitude with the difference (b -h between the upper andlower basepoints of that segment of the station loading schedule whichis in use. A linear proportional relationship between the net inputvoltage and the output voltage of amplifier 211 is insured by thenegative-feedback resistor 21%.

The output voltage of operational amplifier 2E1 is applied across theslidewire 22%) of the computer circuit 122i. The position of thisslidewire relative to its contact 22-2 is determined by the angularposition of shaft 21% of servo-motor 194. Thus, the efiective outputvoltage e or" slidewire 229 is proportional to the quantity u' d) a d)The effective output voltage e of slidewire 228 is applied to theungrounded terminal of the amplifier 225 through the input resistor 224.The output voltage of amplifier 225 is applied to slidewire 226 whosecontact 2-27 is positioned relative thereto in accordance with theangular position of shaft 133 of servo-motor 181. Thus, the effectiveoutput voltage e of slidewire 225 as thus described is proportional tothe quantity (X -X The eiiective output voltage c of slidewire 226 isapplied through input resistor 223 to the ungrounded input terminal ofamplifier 225. Thus, the output voltage o is a negative-feedback voltageWhose magnitude depends upon the feedback factor (X X and the outputvoltage of amplifier 225 represents the quantity After reversal of itspolarity, the output voltage of amplifier 225 is applied through inputresistor to the ungrounded input terminal of amplifier 236. Suchreversal of polarity is effected by the amplifier 231 to whoseungrounded input terminal the output voltage of ampliiier 225 isapplied. The negative-feedback resistor 232 of amplifier 231i insureslinear proportionality of its input and output voltages so that thelatter as applied through input resistor 229 to the ungrounded inputterminal of amplifier 2% represents the quantity To the ungrounded inputterminal of amplifier 23 31 is applied, through input resistor 22?), theoutput voltage of the operational amplifier 2E5 which, as aboveexplained, represents the lower basepoint of that segment or" thestation loading schedule which is in effect. Thus, the net input to theamplifier 23% represents the quantity Because of the reversal ofpolarity efiiected by ampli- .er 23d and because of the linearityinsured by its negatit e-feedback resistor 234, the output voltage G ofamplitier 2% may be expressed by Equation 1 as solved for the desiredgeneration of station S1.

For each additional station of the area, there is a computer networkcorresponding with computer network 221 in which slidewirescorresponding with slidewires 229 and 226 are positioned with respect totheir adjustable contacts by the servomotor shafts 196, 183 respec-- aea tively. Also for each additional station, each of the relays162A-162C is provided with additional sets of contacts for staggeredstepping connection of basepoint s-lidewires to provide for theassociated computer circuit two input voltages, one corresponding withthe difierence b -b of the upper and lower basep-oints of the stationschedule in effect and the magnitude h of the lower basepoint of thatsegment.

In all of the arrangements described, as applied at area level, thedesired allocation of generation among the stations for each segment ofthis area loading schedule is automatically established by presetting ofthe station basepoints alone or by presetting the station basepoints andthe area breakpoints all of which may be calibrated to be direct readingin megawatts or equivalent. None of the arrangements described requiresany presetting of participation slidewires individual to the stations ofthe area. Such advantage also obtains when any of the arrangementsdescribed are utilized at station level for allocation of stationgeneration among the generating units of that station in accordance withmulti-segment unit-loading schedules.

' It will also he understood that the total generation desired from asource may be computed in accordance with the following variation ofEquation 1.

storm-(Gleam To solve this variation of Equation 1 with the arrangementshown in FIGS. 2, 3 or FIG. 5, the area regulation term would be (X -Gas obtained by using the sum of the upper basepoints rather than G Xobtained by using the sum of the lower basepoints and the stationbasepoint included in the computation would be the upper rather than thelower basepoint.

For this variation of Equation 1 with the arrangement shown in FIG. 7,the area breakpoint input of amplifier 186 would be frgrn the upperbreakpoint bus 163 rather than the lower breakpoint bus 164, and thebasepoint input to amplifier 230 would be derived from the upperbasepoint bus 205 rather than from the lower basepoint bus 206.

What is claimed is:

l. A system for allocating the total generation required of a group ofgenerating sources among said sources in accordance withloading'schedules comprising means for producing a variable signalrepresenting the total generation of the group modified by the change intotal generation required to maintain the total generation on schedule,means for producing signals representing the upper and lower basepointgenerations of the individual sources and the sums of the upper andlower basepoint generations of said group of sources, andgeneratiomallocation means for deriving from the aforesaid signals aplurality of generation-allocation signals each representing the desiredgeneration of a source and having two com-ponents, one representing oneof the basepoints of that source and the second representing the productof the deviation of said required total generation from the sum of saidone basepoint and the corresponding basepoints of the remainder of saidsources times the ratio b -upper basepoint of corresponding source b=lower basepoint of corresponding source X =sum of upper basepoints ofall sources X =sum of lower basepoints of all sources 2. A system forallocating the total generation required of a group of generatingsources among said sources in accordance with loading schedulescomprising means for producing a variable signal representing the totalgeneration of the group modified by the change in total generationrequired to maintain the total generation on schedule, means forproducing signals representing the upper and lower basepoint generationsof the individual sources and the sums of the upper and lower basepointgenerations of said group of sources, and generation-allocation meansfor deriving from the aforesaid signals a plurality ofgeneration-allocation signals each representing b =lower basepoint ofcorresponding source b =upper basepoint of corresponding source X =sumof lower basepoints of all sources X =sum of upper basepoints of allsources G otal generation of group N =required change of G 3. A systemfor allocating the total generation required of a group of generatingsources among said sources in accordance with loading schedulescomprising means for producing a variable signal representing the totalgeneration of the group modified by the change in total generationrequired to maintain the total generation on schedule, means forproducing signals representing the upper and lower basepoint generationsof the individual sources and the sums of the upper and lower basepointgenerations of said group of sources, and generation-allocation meansfor deriving from the aforesaid signals a plurality ofgeneration-allocation signals each representing where b =lower basepointof corresponding source b =upper basepoint of corresponding source X=sum of lower basepoints or all sources X =sum of upper basepoints orall sources G =total generation of group N=required change of GA.

4. A system for allocating total generation among generating sources ofa group in accordance with a loading schedule comprising means forproducing a variable signal representative of the total generation to beallocated, means for producing signals representative of the upper andlower basepoint generations of individual sources and the sums of theupper and lower basepoint generations of said group of sources, andgeneration-allocation means for deriving from said signals a pluralityof generationallocation signals each representing the sum of the lowerbasepoint of the corresponding source plus the product of the deviationof the total generation to be allocated from the sum of the lowerbasepoints times the ratio b b X -'-X where b ==lower basepoint ofcorresponding source b =upper basepoint of corresponding source X =sumof lower basepoints of the sources X sum of upper basepoints of thesources.

5. A system for allocating total generation among generating sources ofa group in accordance with a loading schedule comprising means forproducing a variable signal representative of the total generation to beallocated, means for producing signals representative of the upper andlower basepoint generations of individual sources and the sums of theupper and lower basepoint generations of said group of sources, computermeans for deriving from said signals a plurality ofgeneration-allocation signals each representing the product of thedeviation of 'b2 =lower basepoint of corresponding source b =upperbasepoint of corresponding source X =sum of lower basepoints of thesources X =sum of upper basepoints of the sources,

and means for adding to each of said generation-allocation signals asignal representative of the lower basepoint of the corresponding sourceto produce a signal representative of the generation required of thatsource to put it on schedule.

6. A system for allocating total generation among generating sources ofa group in accordance with a loading schedule comprising means forproducing a variable signal representative of the total generation to beallocated, means for producing signals each representative of thedifierence between the upper and lower basepoint generations of acorresponding one of the individual sources, means for producing asignal representative of the difference between the sum of the upperbasepoint generations of said sources and the sum of the lower basepointgenerations of said sources, and generation-allocation means forderiving from said signals a plurality of sig nals each representing theproduct of the deviation of total generation to be allocated from thesum of corresponding ones of the basepoints times the ratio u d u dwhere b b =diiference between upper and lower basepoints ofcorresponding source X X =difi?erence between sums of upper and lowerbasepoints of all sources.

7. A system for allocating total generation among generating sources ofa group in accordance with a loading schedule comprising means forproducing a variable signal representative of the total generation to beallocated, means for producing signals each representative of thedifference between the upper and lower basepoint generations of acorresponding one of the individual sources, means for producing asignal representative of the difference between the sum of the upperbasepoint generations of said sources and the sum of the lower basepointgenerations of said sources, and generation-allocation means forderiving from said signals a plurality of signals each representing theproduct of the deviation of total generation to be allocated from thesum of the lower basepoints times the ratio b b =difference betweenupper and lower basepoints of corresponding source X X =diiferencebetween sums of upper and lower basepoints of all sources.

8. A system for allocating total generation among generating sources ofa group in accordance with a loading schedule comprising means forproducing a variable signal representative of the total generation to beallocated, means for producing signals each representative of thediiference between the upper and lower basepoint generations of acorresponding one of the individual sources, means for producing asignal representative of the difference between the sum of the upperbasepoint generations of said sources and the sum of the lower basepointgenerations of said sources, generation-allocation means for derivingfrom said signals a plurality of signals each rep- 18 resenting theproduct of the deviation of total generation to be allocated from thesum of corresponding ones of the basepoints times the ratio u d u dwhere b -b =difiference between upper and lower basepoints ofcorresponding source X X =difference between sums of upper and lowerbasepoints of all sources,

and means for adding to each of said generation-allocation signals asignal representative of said one basepoint of the corresponding sourceto produce a signal representative of the generation required of thatsource to put it on schedule.

9. A system for allocating total generation among generating sources ofa group in accordance with a loading schedule comprising means forproducing a variable signal representative of the total generation to beallocated, means for producing signals each representative of thedifference between the upper and lower basepoint generations of acorresponding one of the individual sources, means for producing asignal representative of the dilference between the sum of the upperbasepoint generations of said sources and the sum of the lower basepointgen-' erations of said sources, generation-allocation means for derivingfrom said signals a plurality of signals each representing the productof the deviation of total generation to be allocated from the sum of thelower basepoints times the ratio where b b =difference between upper andlower basepoints of corresponding source X X =difference between sums ofupper and lower basepoints of all sources,

and means for adding to each of said generation-allocawhere b -b=difterence between upper and lower basepoints of corresponding source XX =difference between upper and lower breakpoints,

means for producing a variable signal representative of the totalgeneration to be allocated, and means for combining said variable signalwith each of said ratio signals to produce a plurality ofgeneration-allocation signals respectively representative of the extentto which the generation of each of said sources should be above itslower basepoint.

11. A system for allocating total generation among generating sources ofa group in accordance with a loading schedule comprising means forproducing signals representative of the upper and lower basepointgenerations of the individual sources, means for producing fixed signalsrepresentative of the upper and lower group breakpoints, means forderiving from said signals a plurality of ratio signals eachrepresenting the ratio X -X where b b =difference between upper andlower basepoints of corresponding source X X =difference between upperand lower breakpoints,

means for producing a variable signal representative of the totalgeneration to be allocated, means for combining said variable signalwith each of said ratio signals to produce a plurality ofgeneration-allocation signals respectively representative of the extentto which the generation of each of said sources should be above itslower hasepoint, and means for adding to each ofsaidrgeneration-allocation signals a signal representative of the lowerbasepoint of the corresponding source to produce a signal representativeof the generation required of that source to put it on schedule. I

12. A system for allocating the total generation required of a group ofgenerating sources among said sources in accordance with a multi-segmentloading schedule comprising means for producing a variable signalrepresenting the total generation of the group modified by the change intotal generation required to maintain the total generation on schedule,means for producing signals representing the basepoint generations ofthe individual sources and the sums of the basepoint generations of thesources of said groups, switching means responsive to the transition oftotal generation from one schedule segment to the next to select thesignals corresponding with the upper and lower basepoints of said nextschedule segment, and generation-allocation means for deriving from saidvariable signal and the signals selected by said switching means aplurality of generation allocation signals each representing the desiredgeneration of a source and having two components, one representing oneof the basepoints of that source and the other representing the productof the deviation of said required total generation from the sum of saidone basepoint and the E'orresponding basepoints of the remainder of saidsources times the ratio b -b X,,X where b =upper basepoint ofcorresponding source b =1ower basepoint of corresponding source X =sumof upper basepoints of all sources X =sum of lower basepoints of allsources.

13. A system for allocating total generation among generating sources ofa group in accordance with a multisegment loading schedule comprisingmeans for producing a variable signal representative of the totalgeneration to be allocated, means for producing signals representing thebasepoint generations of the individual sources and the sums of thebasepoint generations of said sources, switching means responsive to thetransition of total generation from one schedule segment to the next toselect the signals corresponding with the upper and lower basepoints ofsaid next schedule segment, and generation-allocation mean for derivingfrom said variable signal and the signals selected by said switchingmeans a plurality of generation-allocation signals each representing thesum of the lower basepoint of the corresponding source for the schedulesegment in effect plus the product of the deviation of total generationto be allocated from the sum of the lower basepoints times the ratio 2bwhere bg lower basepoint of corresponding source for schedule segment ineffect 7 b =upper basepoint of corresponding source for schedule segmentin effect X zsum of lower basepoints of the sources for schedule segmentin effect X =sum of upper basepoints of the sources for schedule segmentin effect.

14. A system for allocating total generation among generating sources ofa group in accordance with a multisegment loading schedule comprisingmeans for producing a variable signal representative of the totalgeneration to be allocated, means for producing signals representativeof the basepoint generations of the individual sources and the sums ofthe basepoint generations of said sources, switching means responsive tothe transition of total generation from one schedule segment to the nextto select the signals corresponding with the upper and lower basepointsof said next schedule segment, and generation-allocation means forderiving from said variable ignal and the signals selected by saidswitching means a plurality of generation-allocation signals eachrepresenting the product of the deviation of total generation to beallocated from the sum of the lower basepoints times the ratio where b=lower basepoint of corresponding source for schedule segment in eifectb =upper basepoint of corresponding source for schedule segment ineifect X =sum of lower basepoints of the sources for schedule segment ineifect X =sum of upper basepoints of the sources for schedule segment inefiect,

and means for adding to each of said generation-allocation si nals asignal representative of the lower basepoint of the corresponding sourceto produce a signal representative of the generation required of thaturce to put it on the schedule segment in effect.

15. A computer system for allocating the total output of a group ofsources among said sources in accordance with a schedule comprisingmeans for producing a variable signal varying in accordance with saidtotal output, means for producing signals representing upper and lowerlimits of the outputs of the individual sources and the sums of theupper and lower limits of the sources, and allocation means for derivingfrom the aforesaid signals the desired output of a source and having twocomponents, one representing One of the limits of that source and thesecond representing the product of the deviation of said total outputfrom the sum of one limit and the corresponding limits of the remainderof said sources times the ratio LITE. x x

where b =upper limit of corresponding source b =lower limit ofcorresponding source X =sum of upper limits of said sources X =sum oflower limits of said sources.

16. A computing system for producing an output signal related to avariable quantity'to be kept on a schedule having coordinates along Xand Y axes comprising means for producing a variable signalrepresentative f aid quantity, means for producing signalsrepresentative f the upper and lower limits of said variable quantity onthe X axis and for producing signals representative of the upper andlower limits of said Output signal on the Y axis, and means for derivingfrom said signals an out- 21 put signal which varies in accordance withsaid variable quantity and having two components, one representing oneof said limits on the Y axis and the other representing the product ofthe deviation of said quantity from the corresponding limit on the Xaxis times the ratio X X d where b =upper limit on Y axis b =lower limiton Y axis X =upper limit on X axis X =lower limit on X axis.

17. A system for allocating the generation required of a group ofgenerating sources among said sources in accordance with source outputversus group total output loading schedules having at least one group ofsegments comprising means for presetting said schedules includinghasepoint setters and group breakpoint setters, said setters each beingcalibrated in terms of generation units, said basepoint setters eachproducing a signal representative of a corresponding basepoint andunafiected by any other basepoint setting, said group breakpoint setterseach producing a signal representative of a corresponding breakpoint andunaffected by any other breakpoint setting, means for producing avariable signal representative of the total generation required of saidgroup of sources, and computing means for deriving from said preset andvariable signals a plurality of signals respectively representing thedesired generations of the different sources and each corresponding withbd+( A XdIlZN)(%) where b =lower basepoint of corresponding source forschedule segment in efiect b =upper basepoint of corresponding sourcefor schedule segment in effect 22 X =lower breakpoint of group ofsources for schedule segment in effect X =upper breakpoint of group ofsources for sci edule segment in efiect G =total generation of group ofsources N=required change of G 18. A system for allocating the totalgeneration required of a group of generating sources among said sourcesin accordance with loading schedules comprising means for producing avariable signal representative of the total generation to be allocated,means calibrated in generation units and preset to produce signalsrepresentative of the upper and lower basepoint generations ofindividual sources and the sums of the upper and lower basepointgenerations of said group of sources, computing means for deriving fromsaid variable and preset signals a plurality of signals respectivelyrepresenting the desired generations of the different sources and eachcorresponding with where b =lower basepoint of corresponding source b=upper basepoint of corresponding source X =sum of lower basepoints ofall sources X =sum of upper basepoints of all sources G =totalgeneration of group N=required change of G means for producing signalsrespectively representing the actual generation of the diiferentsources, means for comparing said desired generation signals with saidactual generation signals to produce error signals respec tivelyrepresenting the diiference between the desired generation and actualgeneration of each source, and means for controlling the generation ofeach source to reduce the corresponding error signal to zero.

No references cited.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Noe 3O76,898 February 5 1963 Nathan Cohn It is hereby certified that errorappears in the above numbered patent requiring correction and that thesaid Letters Patent should read as corrected below.

Column 3, line 35, for "present" read preset column 5 line 1-, for"station" read stations column 7, line 2 for "would" read should line 67for "bases" read basis column 9, line 4, for "ll" read lll column ll,lines 18 and 19, for "numbed" read number column l5 lines 26 to 28,, forthat portion of Equation 1 reading "G b read G :b

Signed and sealed this 25th day of February 1964,

(SEAL) Attest:

ERNEST wt, SWIDER EDWINLT, REYNOLDS Attesting Officer ActingCommissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent N00 3,076,898 February 5 1963 Nathan Cohn It is herebycertified that error appears in the above numbered patent requiringcorrection and that the said Letters Patent should read as correctedbelow.

Column 3, line 35, for "present" read preset column 5 line I, for"station" read stations column 7, line 2 for "would" read should line67, for "bases" read basis column 9, line 4, for "11" read lll column11, lines 18 and 19, for "numbed" read number column 15, lines 26 to 28for that portion of Equation 1 reading "Gs-b P680] G ]O Signed andsealed this 25th day of February 1964:.

(SEAL) Attest:

RNEST SWIDER EDWIN Lu REYNOLDS Attesting Officer Acting Commissioner ofPatents

18. A SYSTEM FOR ALLOCATING THE TOTAL GENERATION REQUIRED OF A GROUP OFGENERATING SOURCES AMONG SAID SOURCES IN ACCORDANCE WITH LOADINGSCHEDULES COMPRISING MEANS FOR PRODUCING A VARIABLE SIGNALREPRESENTATIVE OF THE TOTAL GENERATION TO BE ALLOCATED, MEANS CALIBRATEDIN GENERATION UNITS AND PRESET TO PRODUCE SIGNALS REPRESENTATIVE OF THEUPPER AND LOWER BASEPOINT GENERATIONS OF INDIVIDUAL SOURCES AND THE SUMSOF THE UPPER AND LOWER BASEPOINT GENERATIONS OF SAID GROUP OF SOURCES,COMPUTING MEANS FOR DERIVING FROM SAID VARIABLE AND PRESET SIGNALS APLURALITY OF SIGNALS RESPECTIVELY REPRESENTING THE DESIRED GENERATIONSOF THE DIFFERENT SOURCES AND EACH CORRESPONDING WITH